R: How to save two Mitsubishi M2896 drive (spindle motor smoked!)

[Enrico Lazzerini]

I tried to connect a resistor of 10kohm to 3rd wire of the connector but
putting it to ground or to +5vdc nothing happens. I also checked if with a
disk inserted into the drive what kind of signal come out from the 3rd wire
from the main but always remains at zero volts. Checking with the
oscilloscope signals on chips of the spindle motor all seems very stop and
static. I report below some value of voltages misured on the IC's pin and
photos at high resolution at the link below.

https://www.dropbox.com/sh/ozy5mn06hyz9jn1/AADelz2vVsTSEAwmwoVzvwppa?dl=0 

LB1620
Pin1= 18,2V
Pin2= 9,2V
Pin3=0V
Pin4=24v
Pin5=pin6=pin7=0V
Pin8=0V
Pin9=pin19=8,93V

TC9142P
pin1= pin5= Q101Base=3,52v
pin4= pin10= pin16=8,93v
pin6=6,2v
pin7=pin8=3,5v
pin9= NC =3,52v
pin11= Q101collector = 8,97v
pin12= pin13= NC
pin14= pin15= square wave

C358C
pin1=pin2=pin3= 4,5v
pin4=GND
pin5=0,5v connected to the 3rd input wire
pin6= 1,2v connected to the r101 - r105 with the other side of r101
connected to pin 16 of 9142
pin7= 7,76v connected to Q101 collector
pin8= 9v


main link with other info
https://www.dropbox.com/sh/p12w71v69tjgfz7/AAAIReql4Se5ZCkLClPoAVOPa?dl=0

Thanks in advance for your help.

Enrico